1. Field of the Invention
The present invention relates to a laboratory cage and rack system. More specifically, the invention relates to a ventilated rack system, which can substantially eliminate the transfer of contaminants or pathogens between a cage system housed in a rack and the laboratory room in which the rack is located.
2. Description of Related Art
Recently, there has been an increased need for biocontainment, so that high BSL (bio safety level) experiments can be conducted with a minimal risk to the laboratory personnel. Whereas the currently available cage and rack systems maximize the safety of the laboratory animals, there tends to be less focus on protecting the laboratory personnel that handles the cages and the animals from the contaminants and pathogens that may be present in the cages.
There are certain biocontainment cage and rack systems available in the market directed to biocontainment to provide containment of the contaminants and pathogens in the cage. For example, the ISOCAGE™ of Tecniplast, S.p.a., a description of which is provided at http://www.tecniplastusa.com/italframeCP5.html, and IVC Rodent Caging Systems of Allentown Caging Equipment Company provide systems wherein the cage is sealed and air is introduced and removed through valves. In these systems, generally, the rack contains an air supply system for supplying HEPA filtered air into the cages and an air exhaust system for removing air from the cage, thus maintaining a constant airflow of HEPA filtered air within the cage. The cage is kept sealed using a soft seal, such as a silicon seal, which is positioned between the cage top and cage bottom. The rack is an open rack having air plenums for supplying and removing air to and from the sealed cages.
These biocontainment systems may, however, have several drawbacks. For example, the soft seal is removable, either inadvertently or purposefully for cleaning and autoclaving, and can either be improperly positioned when replaced or become shifted from its proper position during use. When any interruption in the seal occurs, either unfiltered ambient air may enter the cage, thus placing the encaged animal at risk, or the unfiltered air from the cage may enter the laboratory room, thus putting the laboratory personnel at risk.
Additionally, because the cages of these currently available biocontainment systems are sealed, if the air supply is removed or stopped, there would be no new air being introduced into the cage. For example, if there is an extended power outage, if the airflow is obstructed, or if supply port becomes blocked, etc., the animal can be deprived of new or recirculated air for an extended period of time. This has the potential to impair the health of the animals. Additionally it does not require serious injury to impair or ruin the experimental reason for housing the laboratory animals. Accordingly, an extended deprivation of air supply in the cage can delay the experiment and hence cause a substantial financial loss for the laboratory.
Accordingly, there is a need to provide a cage and rack system can provide a safe and comfortable environment for laboratory animals as well as the laboratory personnel handling the cage and animals, more particularly, for use in higher level BSL experiments.